상수도용 버터플라이 밸브의 고유 및 유효 유량특성에 관한 연구

Abstract

For standardization of water supply facilities and operation control, we should find out the valve’s inherent and installed flow characteristics. It is true that it has been hard to provide a study of typical valve’s characteristic exactly because there are not enough experimental conditions on large or middle size valve and from small-scale companies. Thus, the primary objective of this paper is to suggest efficient valve control. To achieve this aim the study includes the laboratory test and analytical CFD in order to get results from designing valves and controlling factors with deliberations in the present domestic circumstance. Furthermore, it is effectively willing to give a help to practical-onsite works by clarifying the distinction among the each forms, opening ratio and others with mutual verification of CFD

thus, there is a big difference in supply ability according to trim and disk shape. In addition, the similar result to △=1psi condition from 400A is attained in the case of pipe’s maximum volume flow (Qmax) more than 1500m3/hr during valve opening.

a symmetric disc design valve is Linear characteristic, and Single or double offset design valve which valve seat is fixed with disk is Linear characteristic or fixed with body is Equal Percentage. Moreover, when eccentric type is set to enhance butterfly valve’s throttle, it is getting to be more triple offset design valve so that it has the characteristic like Linear. Those cause the volume flow is easy to adjust. An effective characteristic of volume flow can supply 40%~90% of maximum volume within opening ratio 20% of more than pipe loss Cp=64. Under the less than opening ratio 20% adjusted minutely, each manufacturer shows 10%~90% of maximum volume flow

also, this study derives valve’s characteristic of volume flow from the forms, Inherent Flow Characteristic(Cv) of butterfly valves widely used.

According to the result of comparison between CFD analyses and valve-test values, it shows approximate values each other, and the error rate of Inherent Flow Characteristic (Cv) and lose factor (K) has within maximum values of 6%. Inherent Flow Characteristic (Cv) in the valve-test result shows a similar tendency as generally well-known fact. Also, this shows several characteristics